数据库要运行在归档模式下:
archive log list
shutdown immediate
startup mount
alter database archivelog;
alter database open;
archive log list
热备份users表空间：
(1)实验环境相关信息查看
创建备份路径
mkdir -p /home/oracle/hotbk/
这里为了测试更改归档文件的路径
mkdir /home/oracle/arc_orcl_dest1/ alter system set log_archive_dest_1=‘location=/home/oracle/arc_orcl_dest1/‘; select sequence#,name from v$archived_log; alter system switch logfile; alter system switch logfile; alter system switch logfile; select sequence#,name from v$archived_log;
查看数据文件
SQL> select name from v$datafile; NAME ---------------------------------------------------------------------------------------------------- /u01/app/oracle/oradata/orcl/system01.dbf /u01/app/oracle/oradata/orcl/sysaux01.dbf /u01/app/oracle/oradata/orcl/undotbs01.dbf /u01/app/oracle/oradata/orcl/users01.dbf Elapsed: 00:00:00.00
查看表空间
SQL> select name from v$tablespace; NAME ------------------------------ SYSTEM SYSAUX UNDOTBS1 USERS TEMP Elapsed: 00:00:00.00
查看备份信息
SQL> select * from v$backup; FILE# STATUS CHANGE# TIME ---------- ------------------ ---------- --------- 1 NOT ACTIVE 0 2 NOT ACTIVE 0 3 NOT ACTIVE 0 4 NOT ACTIVE 1027726 27-SEP-16 Elapsed: 00:00:00.00
SQL> select name,file# from v$datafile 2 ; NAME ---------------------------------------------------------------------------------------------------- FILE# ---------- /u01/app/oracle/oradata/orcl/system01.dbf 1 /u01/app/oracle/oradata/orcl/sysaux01.dbf 2 /u01/app/oracle/oradata/orcl/undotbs01.dbf 3 /u01/app/oracle/oradata/orcl/users01.dbf 4 Elapsed: 00:00:00.00
查看文件号及其检查点的编号
SQL> select file#,checkpoint_change# from v$datafile; FILE# CHECKPOINT_CHANGE# ---------- ------------------ 1 1027476 2 1027476 3 1027476 4 1027726 Elapsed: 00:00:00.01
SQL> select file#,checkpoint_change# from v$datafile_header; FILE# CHECKPOINT_CHANGE# ---------- ------------------ 1 1027476 2 1027476 3 1027476 4 1027726 Elapsed: 00:00:00.01
(2)真正开始备份
这里备份users这个表空间。
alter tablespace users begin backup; !cp -v /u01/app/oracle/oradata/orcl/users01.dbf /home/oracle/hotbk/ alter tablespace users end backup;
查看备份点
SQL> select * from v$backup; FILE# STATUS CHANGE# TIME ---------- ------------------ ---------- --------- 1 NOT ACTIVE 0 2 NOT ACTIVE 0 3 NOT ACTIVE 0 4 NOT ACTIVE 1028454 27-SEP-16 Elapsed: 00:00:00.00
(3)模拟数据修改
SQL> select owner,table_name from dba_tables where tablespace_name=‘USERS‘;
create table scott.ob2 as select * from dba_objects;
select count(*) from scott.ob2;
commit;
alter system switch logfile;
查看数据变化情况
SQL> select file#,checkpoint_change# from v$datafile; FILE# CHECKPOINT_CHANGE# ---------- ------------------ 1 1028188 2 1028188 3 1028188 4 1028454 Elapsed: 00:00:00.00 SQL> select file#,checkpoint_change# from v$datafile_header; FILE# CHECKPOINT_CHANGE# ---------- ------------------ 1 1028188 2 1028188 3 1028188 4 1028454 Elapsed: 00:00:00.00
和之前的比较，发现checkpoint_change发生了变化。
查看有没有修复的数据块：
SQL> select * from v$recover_file; no rows selected Elapsed: 00:00:00.00
模拟数据文件损坏
SQL> !rm -f /u01/app/oracle/oradata/orcl/users01.dbf
###### alter system flush buffer_cache;这里不要执行
## startup force
SQL> shutdown immediate; Database closed. Database dismounted. ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 4041949184 bytes Fixed Size 2259520 bytes Variable Size 889193920 bytes Database Buffers 3137339392 bytes Redo Buffers 13156352 bytes Database mounted. ORA-01157: cannot identify/lock data file 4 - see DBWR trace file ORA-01110: data file 4: ‘/u01/app/oracle/oradata/orcl/users01.dbf‘
select * from v$recover_file;
SQL> select * from v$recover_file; FILE# ONLINE ONLINE_ ERROR ---------- ------- ------- ----------------------------------------------------------------- CHANGE# TIME ---------- --------- 4 ONLINE ONLINE FILE NOT FOUND 0 Elapsed: 00:00:00.01
备注：这里4号文件找不到
还原：使用备份的文件代替丢失的文件
cp /home/oracle/hotbk/users01.dbf /u01/app/oracle/oradata/orcl/users01.dbf
再查看一下情况：
SQL> select * from v$recover_file;
FILE# ONLINE ONLINE_ ERROR
---------- ------- ------- -----------------------------------------------------------------
CHANGE# TIME
---------- ---------
4 ONLINE ONLINE
1028454 27-SEP-16
报ERROR错误
恢复：使用备份之后的日志对数据文件进行前滚（把数据修改重现）
recover datafile 4;
SQL> recover datafile 4;
Media recovery complete.
SQL> select * from v$recover_file;
no rows selected
Elapsed: 00:00:00.00
SQL> alter database open;
Database altered.
Elapsed: 00:00:01.43
SQL> select count(*) from scott.ob2;
COUNT(*)
----------
86344
Elapsed: 00:00:00.02
到这里已经搞定了！！！！
写得不好，如果有什么错误请指出，谢谢！！！！